In recent years, environments in which electronic components are used in vehicles as well as in electrical equipment have been diversified. Therefore, environmental resistance is strongly required for electronic components used in electrical equipment and the like. Specifically, electronic components having high mechanical strength and excellent vibration resistance are required. However, cylindrical electronic components such as electrolytic capacitors, electric double layer capacitors, and lithium ion capacitors tend to be vulnerable to vibration because they stand upright on a circuit board and the electrode terminals are fixed by solder or the like.
Therefore, in order to satisfy the requirement, the following forms are implemented. For example, an inner bottom corner portion of a bottomed cylindrical metal case accommodating an element is cladded to form a tapered portion tapering toward the inner bottom surface, the outer periphery of the cylindrical element is covered with a separator longer than the cylindrical length, and the separator protruding from the cylindrical portion is pressed against the tapered portion and crushed, thereby securing the insertion distal end side while protecting the corner portion of the element (see PTL 1).